Need to make sure your safety circuit is all there (nuetral, PTO's, Brake year depending). Could also be the fuze box. My fathers 430 I had an issue and once I put a meter to start reading things it made a connection. The tab that the fuze spade went into was bent too far away. I used the meter prob and bend it back and no issues since. A volt meter will tell you a lot. Check the purple safety wire at the starter to see if there is power. If not-start tracing back till you find where there is a break in power. My one 332 the connector is also a bit loose and requires a wiggle once in a while. Fathers 430 also had a bad nuetral switch when I started working on it.